Evaluation of Climate Change Effects on the Entering Runoff the Makhmalkoh Dam Using the IHACRES Model

In this study, the entering runoff to Makhmalkooh Dam; in Lorestan province; was studied under climate change scenarios. For this using, the data of precipitation, maximum and minimum temperature and sunshine for the study area in the basic time of 1980-2014 were downscaled with LARS-WG6 model and after choosing the IPSL-CM6A-LR-INCA model as the most compatible model with the study area among the 26 models in the sixth IPCC report, precipitation, minimum and maximum temperature and sunshine were estimated for Kakareza station in three times of 2026-2050, 2051-2075 and 2076-2100 under SSP scenarios. After that, the entering runoff to Makhmalkooh dam was estimated in the future periods under the SSP scenarios using the IHACRES model and the results obtained from the previous step. The results of this study showed that the entering runoff the studied dam will decrease on monthly and seasonal scale in all future periods under SSP climate scenarios. The highest runoff in the monthly scale was predicted in October under the SSP5-8.5 scenario, and the lowest decrease was predicted in May under the SSP1-2.6 scenario. On seasonal scale, the highest amount of reduction in entering runoff to the dam was estimated in the autumn season under the SSP5-8.5 scenario, and the lowest amount of reduction was estimated in the spring season under the SSP1-2.6 scenario. The results of this study also showed that the climate change will have significant effect on entering runoff to Makhmalkooh dam and therefore, the impacts of this phenomenon should be considered in water resources development plans to reduce its damages for posterity.